- Australia’s Great Barrier Reef suffers ‘extensive’ coral bleaching, as scientists fear seventh mass bleaching event CNN
- Aerial surveys of Great Barrier Reef ordered after flights confirm mass coral bleaching The Guardian
- Helicopter Surveys Confirm ‘Extensive Coral Bleaching’ In Southern Great Barrier Reef DeeperBlue.com
- Extensive coral bleaching on southern end of Great Barrier Reef after summer of warmer ocean temperatures ABC News
- Great Barrier Reef authority plans full survey after observing extensive coral bleaching WION
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The Mysterious Origins of The Great Barrier Reef May Finally Be Explained : ScienceAlert
Australia’s Great Barrier Reef might never have come to be were it not for the formation of a vast island based mostly on sand.
K’gari, also known as Fraser Island, has the honor of being the world’s largest sand island, covering around 640 square miles (nearly 1,700 square kilometers) just off the southeastern coast of Queensland.
Along with the nearby Cooloola Sand Mass, the mass of forested dunes and beaches forms an unofficial base to the vast reef that sits to its north.
If this terrestrial ‘launching pad’ had never formed, researchers think the masses of sand carried northwards along the coast by ocean currents would have landed right where the reef now sits.
Quartz-rich sands have a way of smothering carbonate-rich sediments, which are necessary for coral development.
Without K’gari in the way to guide sediment off the continental shelf and into the deep, conditions would not have suited the formation of the world’s largest coral reef, experts argue.
The Great Barrier Reef has a confusing origin story. It only formed half a million years ago, long after conditions were appropriate for the growth of coral.
K’gari might be the lost puzzle piece researchers have been searching for. Analysis and dating of sand from the many dunes on the 123 kilometer (76 mile) long island suggest the land mass formed between 1.2 and 0.7 million years ago, just a few hundred thousand years before the Great Barrier Reef came to be.
The island’s presence probably deflected northward currents, researchers explain, providing the southern and central parts of the great barrier reef the reprieve they needed to start growing thousands of kilometers of coral.
K’gari and Cooloola themselves arose from the accumulation of sand and sediment from the south.
Amid periods of ice formation and fluctuating sea levels, researchers suspect sediment around the world ‘suddenly’ became exposed. In successive periods of ice melt and rising oceans, that sediment then got caught up in the currents.
Along the east coast of Australia this probably meant a long northward treadmill of soil and sand tracing the continental shelf.
A slope off the southern coast of Queensland, however, makes the perfect place for sediment to accumulate, and this is right where K’gari and Cooloola are found.
Just south of the sand masses, coral reefs are conspicuously missing.
If researchers are right, that’s probably because the northward currents here are too strong. K’gari and Cooloola break up the long distance dispersal, stopping quartz-rich sands from smothering developing reefs.
“Before Fraser Island developed, northward longshore transport would have interfered with coral reef development in the southern and central [Great Barrier Reef],” researchers write.
Sediment records from the southern Great Barrier Reef support this idea. About 700,000 years ago, there appears to have been an uptick in carbonate content in sediment in this region.
Research on reefs further north is now needed as well, but at least two-thirds of the Great Barrier Reef seems to owe its existence to a wall of sand to the south.
“The development of Fraser Island dramatically reduced sediment supply to the continental shelf north of the island,” the authors argue.
“This facilitated widespread coral reef formation in the southern and central Great Barrier Reef and was a necessary precondition for its development.”
The study was published in Nature Geoscience.
New Island Rises Above Water in South Pacific After Home Reef Volcano ‘Awoke’ Near Tonga
A new island has appeared out of the ocean and is expanding, experts in the South Pacific along with NASA have revealed. An underwater volcano near Tonga that “awoke” on Sept. 10, known as Home Reef, is responsible for the new island after ejecting lava, plumes of steam and ash, and discoloring the surrounding water. The land mass began to appear 11 hours after the initial underwater volcanic explosion and has expanded to just over eight acres in two weeks. Tonga Geological Services on Saturday confirmed the island had risen to around 50 feet above sea level and that while the volcano is continuing to spew steam and ash, it poses a low risk to surrounding communities. According to NASA’s Earth Observatory, the new island is southwest of Late Island, northeast of Hunga Tonga-Hunga Ha‘apai, and northwest of Mo‘unga‘one. Home Reef sits within what is known as the Tonga-Kermadec subduction zone, an area where three tectonic plates are colliding at the fastest converging boundary in the world, NASA said, claiming the location has Earth’s highest density of underwater volcanoes. These new islands can remain in existence for years, NASA said, but are often short-lived.
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Scientists Discover 4,000-Feet Coral Reef In Australian Desert: Report
Australia was surrounded by oceans and rain forests for hundreds of millions of years.
The remnants of a millions of years old coral reef has been discovered in the middle of an Australian desert. The reef has been discovered in the Nullarbor Plain in southern Australia, which has now been transformed into a 76,000-square-mile desert with limestone bedrock, said a report in Newsweek. However, during the Cenozoic era, some 14 million years ago, the reef was believed to be submerged under a tropical ocean.
Scientists from Curtin University’s School of Earth and Planetary Sciences in Perth have identified these coral reefs as a bull’s-eye form in fresh and high-resolution satellite photos, the outlet further said.
The discovery has challenged their prior beliefs that the Nullarbor Plain had never had any features. Milo Barham, co-author and geologist from Curtin University was quoted as saying by Newsweek, “Unlike many parts of the world, large areas of the Nullarbor Plain have remained largely unchanged by weathering and erosion processes over millions of years, making it a unique geological canvas recording ancient history in remarkable ways.”
“Through high-resolution satellite imagery and fieldwork we have identified the clear remnant of an original sea-bed structure preserved for millions of years, which is the first of this kind of landform discovered on the Nullarbor Plain,” Mr Braham added.
According to Newsweek, 18% of Australia is considered to be desert, making it largely arid in contemporary times. However, Australia was surrounded by oceans and rain forests for hundreds of millions of years, including the ocean that once submerged the Nullarbor Plain.
According to a study published in the journal Earth Surface Processes and Landforms, the coral reef structure includes a circular raised rim and a centre dome shape. The structure has a diameter of 3,950 to 4,250 feet.
The structure also differs from other plain landforms and cannot be described by any of the local geological processes, as per the study, Newsweek further said.
Mystery 4,000-Foot Coral Reef Found in the Middle of the Desert
The remains of a multimillion-year-old coral reef have been discovered in the middle of a desert in Australia.
Southern Australia’s Nullarbor Plain, where the reef was found, is now a 76,000-square- mile desert consisting of limestone bedrock. But it was covered by a tropical ocean about 14 million years ago, during the Cenozoic period.
Researchers from the Timescales of Mineral Systems Group at Curtin University’s School of Earth and Planetary Sciences in Perth spotted the reef as a bull’s-eye shape on new high-resolution satellite imagery. The discovery challenged their previous assumptions that the Nullarbor Plain had always been featureless.
“Unlike many parts of the world, large areas of the Nullarbor Plain have remained largely unchanged by weathering and erosion processes over millions of years, making it a unique geological canvas recording ancient history in remarkable ways,” co-author and geologist Milo Barham of Curtin University said in a statement.
“Through high-resolution satellite imagery and fieldwork we have identified the clear remnant of an original sea-bed structure preserved for millions of years, which is the first of this kind of landform discovered on the Nullarbor Plain,” Barham said.
Curtin University School of Earth and Planetary Sciences / Timescales of Mineral Systems Group
Most of Australia has been dry in modern times, with 18 percent of the country classified as desert. But for hundreds of millions of years, Australia was covered with rain forests and seas, including the ocean that once put the Nullarbor Plain underwater.
The coral reef structure has a circular elevated rim and a central dome shape, according to a paper published in the journal Earth Surface Processes and Landforms. The structure is between 3,950 and 4,250 feet in diameter.
In addition, the structure is distinct from other landforms observed on the plain and cannot be explained by any of the geological processes common to the area, the paper said.
“The ring-shaped ‘hill’ cannot be explained by extra-terrestrial impact or any known deformation processes but preserves original microbial textures and features typically found in the modern Great Barrier Reef,” Barham said.
The researchers’ access to new high-resolution satellite imagery has allowed them to spot much more subtle features of the Nullarbor Plain. This led them to realize it wasn’t a featureless and unchanging landscape, which they had thought it became after its ocean dried up.
“Evidence of the channels of long-vanished rivers, as well as sand dune systems imprinted directly into limestone, preserve an archive of ancient landscapes and even a record of the prevailing winds,” Barham said.
“And it is not only landscapes. Isolated cave shafts punctuating the Nullarbor Plain preserve mummified remains of Tasmanian tigers and complete skeletons of long-extinct wonders such as Thylacoleo, the marsupial lion,” he said.
Curtin University School of Earth and Planetary Sciences / Timescales of Mineral Systems Group
Further exploration of the geology of Nullarbor may aid researchers in their quest to learn more about the beginnings of our solar system and of Earth itself.
“At the surface, due to the relatively stable conditions, the Nullarbor Plain has preserved large quantities of meteorites, allowing us to peer back through time to the origins of our solar system,” Barham said.
“These features, in conjunction with the millions of years old landscape features we have now identified, effectively make the Nullarbor Plain a land that time forgot and allow a fascinating deeper understanding of Earth’s history,” he said.
Parts of Australia’s Great Barrier Reef show highest coral cover in 36 years
MELBOURNE/SYDNEY, Aug 4 (Reuters) – Two-thirds of Australia’s Great Barrier Reef showed the largest amount of coral cover in 36 years, but the reef remains vulnerable to increasingly frequent mass bleaching, an official long-term monitoring programme reported on Thursday.
The recovery in the central and northern stretches of the UNESCO world heritage-listed reef contrasted with the southern region, where there was a loss of coral cover due to crown-of-thorns starfish outbreaks, the Australian Institute of Marine Sciences (AIMS) said in its annual report.
“What we’re seeing is that the Great Barrier Reef is still a resilient system. It still maintains that ability to recover from disturbances,” AIMS monitoring programme leader Mike Emslie told Reuters.
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“But the worrying thing is that the frequency of these disturbance events are increasing, particularly the mass coral bleaching events,” he said.
The report comes as UNESCO considers whether to list the Great Barrier Reef as “in danger”, following a visit by UNESCO experts in March. The World Heritage Committee meeting where the fate of the reef was on the agenda was due to be held in Russia in June but was postponed.
Assorted reef fish swim above a staghorn coral colony as it grows on the Great Barrier Reef off the coast of Cairns, Australia October 25, 2019. REUTERS/Lucas Jackson
In a key measure of reef health, AIMS defines hard coral cover of more than 30% as high value, based on its long-term surveys of the reef.
On the northern region, average hard coral cover grew to 36% in 2022 from a low of 13% in 2017, while on the central region hard coral cover increased to 33% from a low of 12% in 2019 – the highest levels recorded for both regions since the institute began monitoring the reef in 1985.
In the southern region, however, which generally has higher hard coral cover than the other two regions, cover fell to 34% in 2022 from 38% a year earlier.
The recovery comes after the fourth mass bleaching in seven years and the first during a La Nina event, which typically brings cooler temperatures. While extensive, the institute said, the bleaching in 2020 and 2022 was not as damaging as in 2016 and 2017.
On the down side, the growth in cover has been driven by Acropora corals, which AIMS said are particularly vulnerable to wave damage, heat stress and crown-of-thorns starfish.
“We’re really in uncharted waters when it comes to the effects of the bleaching and what it means moving forward. But as of today, it’s still a fantastic place,” Emslie said.
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Reporting by Sonali Paul in Melbourne and James Redmayne in Sydney; Editing by Stephen Coates
Our Standards: The Thomson Reuters Trust Principles.
Australia pledges $700 million to protect Great Barrier Reef amid climate change threat
Prime Minister Scott Morrison unveiled the nearly decade-long conservation package days ahead of a February 1 deadline set by UNESCO to submit a report on the reef’s state of conservation.
“We are backing the health of the reef and the economic future of tourism operators, hospitality providers and Queensland communities that are at the heart of the reef economy,” Morrison said in a statement.
The funding will support new climate adaptation technology, investment in water quality programs, and protect key species in the biodiverse reef, he added.
In July, UNESCO debated whether the Great Barrier Reef was “in danger” — a designation which means a site is under threat. If action wasn’t taken to address concerns, it was at risk of losing its World Heritage status, the UN agency warned.
In a letter published last July, 13 public figures — actors, former politicians and journalists — urged leaders to act fast and “save” the reef.
“We urge the world’s major emitters to undertake the most ambitious climate action under the Paris Agreement,” the letter read. “There is still time to save the Great Barrier Reef, but Australia and the world must act now.”
Morrison’s announcement Friday comes ahead of a general election expected in May.
The Australian Climate Council, which is independent of the government, dismissed Morrison’s pledge, calling it “a band-aid on a broken leg” in a statement Friday.
“Unless you are cutting emissions deeply this decade the situation on the Reef will only get worse,” climate scientist and Professor of Biology at Macquarie University, Professor Lesley Hughes said in the statement.
In an interview with radio station 4A Cairns Friday, Morrison said emissions were falling under policies the government has put in place, which is beneficial for the reef.
“We’re achieving those outcomes, and we’re going to keep doing it because we’re passionate about it,” he said.
Impact of the climate crisis
The Great Barrier Reef, the world’s largest coral reef, covers nearly 133,000 square miles (344,000 square kilometers) and is home to more than 1,500 types of fish, over 400 kinds of hard corals and dozens of other species.
But the effects of the climate crisis, coupled with a series of natural disasters, have had a devastating impact on the reef. An Australian government five-year survey in 2019 found the condition of the natural wonder had deteriorated from “poor” to “very poor.”
The reef has lost 50% of its coral populations in the last three decades, according to a study published in October 2020 by researchers from the ARC Centre of Excellence for Coral Reef Studies.
In a report published in June last year, a UNESCO monitoring mission said that despite the Australian government’s work to improve the reef’s situation, “there is no possible doubt that the property is facing ascertained danger.”
But the Australian government has strongly objected to that conclusion. Environment Minister Sussan Ley flew to Europe last July as part of a last-ditch attempt to convince the other members of the World Heritage to vote against the measure. Australia is currently part of the 21-country rotating committee.
Morrison on Friday called the reef the “best managed” in the world.
“Today we take our commitment to a new level,” he said.
‘Like a work of art’: rare stretch of pristine coral reef discovered off Tahiti | Coral
A huge coral reef has been discovered off the coast of Tahiti in the Pacific Ocean’s “twilight zone”, offering hope that more pristine ecosystems are waiting to be discovered at unexplored depths.
Stretching along the ocean floor for nearly 2 miles, the reef, covered in rose-shaped corals, is one of the largest such discoveries at depths of more than 30 metres, where sunlight levels are much lower.
Scientists for the Unesco-led mission in French Polynesia said the reef, discovered in November, did not appear to have suffered bleaching events that had damaged neighbouring reefs in shallower waters in 2019. During dives totalling 200 hours, researchers were able to witness the coral spawning, with some spanning 2 metres.
“It was magical to witness giant, beautiful rose corals which stretch for as far as the eye can see,” said Alexis Rosenfeld, a French underwater photographer who was part of the team of international divers that made the discovery. “It was like a work of art.”
Researchers said more reefs were likely waiting to be discovered at these depths following improvements in diving technology, which had previously inhibited exploration.
“To date, we know the surface of the moon better than the deep ocean. Only 20% of the entire seabed has been mapped,” said Audrey Azoulay, Unesco’s director general.
Most of the world’s known coral reefs are at depths of 25 metres and above, with many facing the risk of collapse as the world’s oceans continue to heat. In September, a study found coral reef coverage had fallen by half since the 1950s because of global heating, overfishing, pollution and habitat destruction.
Speaking to the BBC Prof Murray Roberts, a marine scientist at the University of Edinburgh, said the discovery underscored the need to map similar reefs to make sure they can be protected in the future.
“We still associate corals with the shallowest tropical seas but here we find a huge previously unknown coral reef system.
“As shallow waters warm faster than the deeper waters we may find these deeper reef systems are refuges for corals in the future. We need to get out there to map these special places,” he said.
Further dives are planned in the coming months off the coast of Tahiti to continue investigations around the reef.
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Rare coral reef discovered near Tahiti in ocean’s ‘twilight zone’
That a coral reef so large and so beautiful had yet to be discovered emphasizes how little we still know about the world’s oceans, scientists say. And its impeccable condition — with no evidence that the reef has yet been harmed by the climate crisis — suggests the need for urgent action to protect the ocean’s remaining healthy reefs.
Alexis Rosenfeld, the photojournalist who led the team of international divers, said the reef, which stretched “as far as the eye can see,” was “magical to witness.”
“It was like a work of art,” he said.
The research mission, led by UNESCO, found the reef stretches for nearly two miles and exists at depths down to 70 meters, or 230 feet. This is around the ocean’s “twilight zone,” where there’s just enough light to sustain life, and below which the ocean transitions into a dark abyss.
“For once, it’s a positive story about coral reefs in the news, which is quite rare these days,” Julian Barbiere, head of marine policy at UNESCO, told CNN.
Warming oceans and acidification caused by the climate crisis has led to widespread coral bleaching. Last year, scientists found the global extent of living coral has declined by half since 1950 due to climate change, overfishing and pollution.
The outlook is similarly grim, with scientists predicting about 70% to 90% of all living coral will disappear in the next 20 years.
Only around 20% of the ocean floor has so far been mapped, according to UNESCO. And until its latest discovery, the vast majority of the planet’s known coral ecosystems were believed to extend to a depth of just 25 meters, illustrating how much of the ocean — which covers more than 70% of Earth’s surface — still needs to be explored.
“The discovery suggests that there are, in fact, many more large reefs out in our ocean at depths of more than 30 meters, which have not been mapped,” Barbiere said. “It’s quite a puzzling finding.”
“While we are witnessing major investment in space exploration, there’s not enough on studying our own home and the ocean in particular,” Barbiere said. “And I think this is really where we want to put our emphasis in the next 10 years — to create the knowledge we need to put the planet on the sustainable path through marine protected areas.”
Despite its depth, researchers say the newly discovered reef still receives enough sunlight for the corals to grow and reproduce. Some of the divers even witnessed the corals spawning.
Researchers went into the mission in November last year with little knowledge of the reefs existing in the region, and came out with an incredible understanding of how widespread, unique and pristine the coral there is.
Using scuba rebreathers, which filter carbon dioxide out of exhaled air and recycle much of the unused oxygen, the dive team was able to spend about 200 hours studying the reef. Rebreathers allow divers to go deeper into the ocean floor and stay for longer periods of time. The rebreathers contain a special helium-based gas mixture that guards against narcosis or a state of drowsiness.
Barbiere said researchers were surprised to learn that the coral was fully intact and healthy, a sign they’ve survived for decades, given large reefs take roughly 25 to 30 years to expand and flourish.
The UNESCO team plans to study the reef more to learn how the coral has thrived for so long in the face of increasingly hostile ocean conditions, in hopes that it may hold the secret to saving endangered reefs.
“We think that deeper reefs may be better protected from global warming,” said Laetitia Hédouin, a marine biologist with the French National Centre of Scientific Research and the environmental research center CRIOBE. “So the discovery of this reef in such a pristine condition is good news and can inspire future conservation.”
Coral reefs under threat
Coral reefs are crucial to Earth’s biodiversity. They are an important food source, as well as habitat, for a wide array of marine organisms. But human-caused climate change threatens these ecosystems around the globe.
Roughly 4,000 miles west of Tahiti, off the coast of Australia, the Great Barrier Reef — the largest reef system in the world — has suffered several large-scale coral bleaching events over the past two decades due to extreme ocean warming. A 2021 study found 98% of the reef had been impacted by bleaching since 1998. And despite having adapted to higher heat thresholds, the study found the corals now have less time to recover between more frequent bleaching events.
Though the Tahiti reef appears healthy right now, there’s still concern that the effects of climate change will reach it, said Steven Mana’oakamai Johnson, a postdoctoral research scholar and marine scientist at Arizona State University.
“Just because the reef currently doesn’t show any impacts from climate change, it doesn’t mean that’s going to hold into the future,” Johnson told CNN. “And so we can’t just assume that because no one knew it was there, and when we found it, it was in good shape that it will continue to dodge the proverbial climate bullets.”
Johnson’s recent research found that 60% to 87% of the world’s oceans are expected to experience devastating biological and chemical changes, including higher levels of acidity and shifts in oxygen levels by 2060, which would drastically harm the planet’s vast coral reefs.
In a special report on oceans in 2019, the UN Intergovernmental Panel on Climate Change concluded with high confidence that the impact on marine ecosystems will worsen if fossil fuel emissions continue at-pace.
Even if global warming is limited to 1.5 degrees Celsius — the ideal goal of the Paris Agreement — “coral reefs are projected to suffer significant losses of area and local extinctions,” scientists reported, noting that efforts to restore them will likely be futile at that point, given the enormous stress they are already under.
“The big takeaway is that [the UNESCO team] found this track of reef that’s in good condition, which definitely speaks to how little we’ve done to truly map the ocean,” said Johnson, who is not involved with the research. “This emphasizes the importance of passing meaningful climate policy including finding ways to support the traditional stewards of these oceanscapes.”
Barbiere said more expeditions have been planned for the coming months to investigate the reef, particularly to study how it has thrived around the ocean’s twilight zone.
An international network of governments, ocean scientists and volunteers are on a mission to map the world’s seabed by 2030 to better understand not only the impacts of the climate crisis, but to improve tsunami warning systems. Studying the ocean, according to Barbiere, could lead to similar discoveries at deeper depths that would require more extensive protection.
“You can only protect what you can measure,” Barbiere said. “And as we are trying to set targets for global ocean conservation around the world, this is the basic information that we need to start establishing marine protected areas.”
Spectacular Coral Event This Year Spawns Hope –And Billions of Babies For Great Barrier Reef (LOOK)
Oceanographers enjoyed a burst of color and life flowing forth in the annual spawning of coral from the Great Barrier Reef last week.
Taking place after the November full moon, researchers witnessed a banner year that inspired hope for the revitalization of the world’s coral reefs.
At the iconic reef off the coast of Cairns, Queensland, different corals synchronized the release of their sperm and eggs, which look almost like the shaking of a giant snow globe.
The coral offspring floated in waves of vivid pink, purple, or blue, depending on the species—and this year it was uniquely impressive.
“Unbelievably beautiful spawning from last night! The party sure has started and the corals are going off,” Reef Teach exclaimed on Twitter, posting a video (see below).
Billions of new coral babies born are good news for the reef, after a difficult few years.
“It is gratifying to see the reef give birth. It’s a strong demonstration that its ecological functions are intact,” Reef Teach marine scientist Gareth Phillips told EcoWatch.
LOOK: Gigantic 438-Year-old Coral Discovered in the Great Barrier Reef in ‘Excellent Condition’
Phillips has spent the past 10 years watching coral spawning.
“The conditions were magical with the water like glass and beautiful light coming from the moon,” he said.
CHECK OUT: Breathtaking Photos of Poppy Field’s First Bloom in Years
He was very reassured when he saw a lot of spawning, “it is a sign that there is recovery underway, that the system is working.”
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MORE: Sanctuary Containing ‘Healthiest Coral Reefs in the World’ Just Tripled in Size Thanks to U.S. Government Protection